A Wooly Bear of a Caterpillar

If you enjoy climbing the cliffs of Bodega Head on the Sonoma coast, keep your eyes out for bears--wooly bear caterpillars, that is.

The so-called "wooly bear caterpillar" is reddish, black and woolly and has a voracious appetite much like that of Joey Chestnut. It is the Ranchman's Tiger Moth caterpillar, Platyprepia virginalis, now changed to Arctia virginalis. 

Richard "Rick" Karban, professor of entomology at the University of California, Davis, studies this critter. "It has a taste for most alkaloid containing plants, like fiddleneck, although it doesn't appear to sequester the alkaloids," he told us. "The alkaloids may help caterpillars survive their parasitoids, however."

We saw about five of the wooly bear caterpillars on a public trail near the Bodega Marine Reserve above the Bodega Marine Laboratory on April 17.

The reserve, which surrounds the Bodega Marine Laboratory, is a unit of the University of California Natural Reserve System and is administered by UC Davis.

Several wooly bear caterpillars were munching on fiddleneck. Another rolled around near a patch of California poppies and we couldn't tell what its menu included. It looked good, though!

You can read Karban's research on "Diet Mixing Enhances the Performance of a Generalist Caterpillar, Platyprepia virginalis," published last February in the Ecological Entomology journal.